The present invention relates to a compact apparatus for measuring the flow of fluid through a conduit by sensing temperature differential at selected locations of the tube relative to a location on the tube where the temperature can be changed.
The general principle of passing a fluid, such as a gas, through a tube and determining the shift in the temperature profile of the tube on opposite sides of a location where the temperature can be varied has been known. It is also known that the extent of the shift is indicative of the flow rate, but the range of flow rates across which prior devices have been useful is limited.
My U.S. Pat. No. 4,972,707 shows a flow meter which provides for accurate measurements across a wide range of flows which can be used for both liquid and gaseous flows.